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Post by garbulky on Dec 9, 2016 16:48:56 GMT -5
I don't know the specifics of the chip. But...in hospital use, if something is specified as needing a certain amount of time before beginning operation, then I assume it's done in such a way. However, the "acceptable time for operation" and optimal functioning time could be two different things. I don't assume that it is like I said it, a DAC chip will not mis-calculate things based on it's operating temperature as long as it is within the operating range. For the DAC chips used in the multibit Gungnir that is -40 to +125 C. I think that's different from what I am talking about regarding warm up. The Gungnir MB will operate fine within those room temperature they specified it for..... Maybe ask the guy that designed the world's first DAC why he says what he says. What I say is that there is an audible difference as it warms up. The designers say it, the reviewers say it, and most of the users say it.
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Post by Boomzilla on Dec 9, 2016 16:51:40 GMT -5
OK - Even if the actual digital-to-analog conversion is "bit-perfect" immediately after turn-on, there are other parts of the DAC - The "anti-jitter-input-buffer," the "reclocker," the "low-pass output filter," and the "analog output buffer." There may be more, but those are the ones that I'm pretty sure exist...
Do THOSE also function "perfectly" immediately on cold turn-on?
And if by "perfectly," we mean "measure perfectly" (as in "within manufacturer's specs"), then we know exactly nothing. Why? Because the cheapest $19.99 DAC and the most expensive one BOTH meet spec - But they sound differently despite their identical frequency-response measurements. So what have we "measured," and why doesn't that tell us more about how the DACs will sound?
Pretty obviously, something is going on that frequency response and distortion measurements ARE NOT CATCHING.
In fact, there's a good article in this month's Absolute Sound magazine that delves into why we can instantly tell the difference between live and recorded music.
But if measurements were significant for DACs, then we could all buy a $19.95 Behringer and be happy as clams. But since we DO hear differences, and those differences become MORE profound with warm-up / burn-in time, then despite the "we know everything about audio that there is to know" faction, there are obviously some things that we don't yet know how to measure.
Boom
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Post by qdtjni on Dec 9, 2016 16:52:51 GMT -5
I don't assume that it is like I said it, a DAC chip will not mis-calculate things based on it's operating temperature as long as it is within the operating range. For the DAC chips used in the multibit Gungnir that is -40 to +125 C. I think that's different from what I am talking about regarding warm up. The Gungnir MB will operate fine within those room temperature they specified it for..... Maybe ask the guy that designed the world's first DAC why he says what he says. What I say is that there is an audible difference as it warms up. The designers say it, the reviewers say it, and most of the users say it. I'm not saying that the sound doesn't change with temperature, in fact I believe it can. Even the DAC chips analogue output can change with temperature drift but if the drift was that large, the chip could never be used in medical applications.
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Post by qdtjni on Dec 9, 2016 16:57:02 GMT -5
OK - Even if the actual digital-to-analog conversion is "bit-perfect" immediately after turn-on, there are other parts of the DAC - The "anti-jitter-input-buffer," the "reclocker," the "low-pass output filter," and the "analog output buffer." There may be more, but those are the ones that I'm pretty sure exist... Do THOSE also function "perfectly" immediately on cold turn-on? I would think that this device can surely sound different at different temperatures. I have certainly perceived that with lots of other devices, then again that might be expectation bias.
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Post by Boomzilla on Dec 9, 2016 17:03:33 GMT -5
Hi qdtjni - I agree with you that devices can sound differently at different temperatures. But those "different sounds" don't seem to be frequency or distortion related. In other words, they are being heard - but can't yet be measured. The DAC will measure absolutely identically (for frequency & distortion) cold as it will hot. Yet the ears are adamant that there is a difference. I don't think it is expectation bias either.
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Post by brutiarti on Dec 9, 2016 17:12:14 GMT -5
Gar, just to clarify is the first "outboard" DAC
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Post by monkumonku on Dec 9, 2016 17:12:47 GMT -5
Hi qdtjni - I agree with you that devices can sound differently at different temperatures. But those "different sounds" don't seem to be frequency or distortion related. In other words, they are being heard - but can't yet be measured. The DAC will measure absolutely identically (for frequency & distortion) cold as it will hot. Yet the ears are adamant that there is a difference. I don't think it is expectation bias either. Maybe it is a matter of your ears warming up to the sound? You start out with expectation bias and when the actual sound doesn't match it, you have a lack of congruence until your ears adjust. Or maybe the sound really does change. But the human mind is something to be reckoned with. Get several people in the room and then upon initial playing, have them write down their impressions of the sound. After the device has "warmed up" a bit, then have them write down their impressions. Then compare impressions to see if they all changed in a similar manner. If the device really does change in sound, then that ought to be consistently observed when comparing each others impressions.
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Post by qdtjni on Dec 9, 2016 17:14:26 GMT -5
Hi qdtjni - I agree with you that devices can sound differently at different temperatures. But those "different sounds" don't seem to be frequency or distortion related. In other words, they are being heard - but can't yet be measured. The DAC will measure absolutely identically (for frequency & distortion) cold as it will hot. Yet the ears are adamant that there is a difference. I don't think it is expectation bias either. If we're talking about DAC as the whole device and not just the DAC chips, I'm not convinced it measures identical cold and up in working temp. Usually when measured, the devices are up in working temp or even driven to the extrem in the case of amps. So it may well be a measurable difference, only that is most certainly not down to the DAC chip.
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Post by gzubeck on Dec 9, 2016 17:15:10 GMT -5
Ugh...there's nothing worse than a cold solid state amp. It takes awhile for the electrons to flow and move faster through the components. Just listening to my dac and amp two hours after warm up is buttery smooth. It's faster smoother boozer...
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Post by qdtjni on Dec 9, 2016 17:21:15 GMT -5
It should be noted that in the quote above, Mike Moffat was referring to physical changes in passive components from burn-in.
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Post by qdtjni on Dec 9, 2016 17:25:22 GMT -5
Gar, just to clarify is the first "outboard" DAC Not even that, at best the first outboard DAC for Hifi. No that it makes him less of an authority in his field.
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Post by gzubeck on Dec 9, 2016 17:29:42 GMT -5
It should be noted that in the quote above, Mike Moffat was referring to physical changes in passive components from burn-in. Burn-in off the impurities and chemicals on wires and components...
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Post by vneal on Dec 9, 2016 17:57:19 GMT -5
I swear music sounds better late at night. Maybe it is my state of mine, maybe it's the wine, maybe it's the electrical power
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Post by qdtjni on Dec 9, 2016 17:58:08 GMT -5
I swear music sounds better late at night. Maybe it is my state of mine, maybe it's the wine, maybe it's the electrical power Whatever it is, it works for me to.
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Post by Boomzilla on Dec 10, 2016 13:54:20 GMT -5
Been listening to my ST-120 in triode mode vs. ultra linear mode. My conclusion - not much difference. Of the two, I think I prefer pentode mode because it seems to have slightly more dynamics (but the difference is so small that I probably couldn't tell in a double-blind test). My Heathkits had dynamics galore (and yes, I could tell in a double-blind test - and so could you), but not a very flat frequency response. The ST-120 has a flatter frequency response, but not as much dynamics. So going with pentode mode brings back a little of the dynamics, but not all. The PT-100 preamp also helps restore some dynamics (but only when using its own internal DAC - and only when running coaxial input - not optical TOSLINK). With pentode mode AND the PT-100, I'm getting sound that I can definitely enjoy big-time. The $8K Audio Research tube power amp is on its way for review. How will it stack up against the ST-120? Enquiring minds want to know! Once the amp arrives, I'm going to have to relieve garbulky of the Schiit Gungnir. Despite the quality & value of the PT-100, I can't test an $8K amp with a $299 DAC/preamp. No matter what I heard, skeptics would claim that any shortcoming was due to the PT-100, not the power amp. So options will be: Oppo BDP 105 with its own DAC & volume control wired directly to the amp via XLRs Schiit Gungnir to the PS Audio preamp to the amp via XLRs Or, if I can come up with other options... Boom
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Post by garbulky on Dec 10, 2016 13:56:45 GMT -5
Once the amp arrives, I'm going to have to relieve garbulky of the Schiit Gungnir. Oh darn....I knew I shouldn't have been talking it up so much! I thought I had till January!
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Post by Boomzilla on Dec 10, 2016 14:07:24 GMT -5
Depends on when the amp arrives...
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Post by vneal on Dec 11, 2016 9:06:57 GMT -5
Option two would be my choice for the AR amp
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Post by gzubeck on Dec 11, 2016 14:07:21 GMT -5
Once the amp arrives, I'm going to have to relieve garbulky of the Schiit Gungnir. Oh darn....I knew I shouldn't have been talking it up so much! I thought I had till January! You do realize that hes letting you fully break in the dac for him for free dont you! Evil Snicker.....
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Post by Boomzilla on Dec 11, 2016 14:39:44 GMT -5
And I may loan him more equipment to break in as well!
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